Device for applying liquid on rail

ABSTRACT

There is provided a device for applying liquid on a rail capable of minimizing wasteful flowing down of expensive application liquid to suppress the total amount of discharge of the liquid, reducing costs and further suppressing occurrence of environmental contamination, and preventing slippage of a wheel due to excessive liquid application. The device for applying liquid on a rail includes a tank, a liquid discharge pump for receiving supply of application liquid from the tank and performing a liquid discharge operation as a wheel passes, and a liquid application unit for discharging the application liquid onto a rail upon being supplied with the liquid from the liquid discharge pump. The liquid application unit has a nozzle block  40  having a large number of nozzle holes  43  arranged in the upper surface of the nozzle block, and the nozzle block  40  has on its end section a hole-less end section  40   a  where no nozzle hole is provided. The nozzle block  40  is pressed and supported from diagonally below by a nozzle block support device  50  that holds a base of the rail from below in such a way that the rail-side edge  40   b  of the top surface of the nozzle block  40  is always in close contact with the tread of the rail.

TECHNICAL FIELD

The present invention relates to a device for applying liquid on a rail, and more particularly to a device for applying liquid on a rail at locations, such as a curve, where the contact pressure between a wheel and a rail becomes high and hence squeak noise is generated (in particular, on the inner-track rail side where wheel tread skid occurs) in order to reduce the noise and prevent wear of the rail and the wheel.

BACKGROUND ART

Triggered by recent subway derailment accidents, more efforts have been made to prevent multiple-factor derailment of railway vehicles and more measures have been taken to safely operate railway vehicles. Examples of the efforts and measures include grinding for restoring rail shapes and modification of the wheel flange angle from 60 degrees to 70 degrees. These measures aim to increase the frictional resistance between the rail and the wheel so as to enhance the margin against flange climb derailment. When these measures are taken, it is conceivable that, particularly at a curve of a rail, more wear of the wheel flange and the rail is generated than that currently generated (on the outer track side, in particular) and the squeak noise increases (on the inner track side, in particular). It is thus conceivable that maintenance and management costs for rails, wheels, tracks and the like increase and there is a need to take measures against noise than ever.

At a curve, when a wheel on one axle is considered, the rolling distance of the outer track-side wheel is longer than that of the inner track-side wheel. The inner track-side wheel thus turns without load (skidding) on the inner track rail and hence generates substantial squeak noise.

As measures against the squeak noise, grease or water is manually applied on the tread-side surface of a rail. Since this operation takes labor and cost, there has been proposed a motorized device for applying oil on a rail characterized in that the rail is provided with an oil injection device having oil injection holes toward the wheel flange of a vehicle traveling on the rail; the oil injection device communicates with an oil reservoir via a motorized pump; the motorized pump is electrically connected to an approaching vehicle detector via a discharge amount controller including a timer mechanism; and oil is applied on the rail from the oil injection holes of the oil injection device in response to a signal from the approaching vehicle detector (Japanese Utility Model Publication No. 53-10641).

The device for applying oil on a rail, however, is motorized and has a large number of components, so that the mechanism is complex, resulting in disadvantages of increased cost for the device itself and running cost, oil sludge attached on the tread and the sides of the rail due to frequent and excessive oil application, labor for removing the oil sludge, and contamination of the surroundings due to use of a large amount of grease and hence possible environmental problems.

To eliminate such disadvantages, there has been proposed a device for applying liquid on a rail including, an oil tank, an oil pump for receiving supply of application liquid (lubricating oil) from the oil tank and performing oil transportation under the treading pressure of a wheel, and a liquid application unit for discharging the application liquid onto a rail upon being supplied with the application liquid from the oil pump (Japanese Patent Laid-Open No. 2002-275806 and No. 2003-127858).

Japanese Patent Laid-Open No. 2003-127858 discloses an oil application unit including a nozzle block 140. The top surface of the nozzle block 140 is slightly inclined downward from the outer side toward the rail side in the width direction, and the rail-side end section is disposed such that it is substantially flush with the rail (see FIG. 9). An oil storage pipe 141 with openings 142 formed at fixed intervals is buried in the nozzle block 140, and nozzle holes 143 that communicate with the openings 142 and are open through the top surface of the nozzle block 140 are formed in the nozzle block 140 in such a way that the nozzle holes 143 are inclined toward a rail 132 by about 45 degrees. The nozzle block 140 is supported on a bracket 149 from below and fixed to the rail via a securing leg 148 having an L-shaped cross section.

When a train approaches and the treading pressure of the wheel is applied to the oil application unit, a check valve is opened and the application liquid is pumped and discharged from a discharge port 146 at the tip of an oil tube 145 into the oil storage pipe 141. Accordingly, part of the application liquid filled in the oil storage pipe 141 is pushed out from the openings 142 of the oil storage pipe 141 into the nozzle holes 143 and supplied on the rail.

The nozzle holes 143 in the conventional nozzle block 140 are formed throughout the length of the nozzle block 140, so that the application liquid discharged from the nozzle holes 143 located at the downstream-side end section in the direction in which the train is traveling tends to immediately flow down from the top surface of the rail. In particular, when the rail is installed on a slope so that the rail is inclined, the above tendency is pronounced. To keep an appropriate amount of the application liquid on the rail, an excessively large amount of application liquid will be supplied. However, the application liquid used for this purpose is an expensive water-soluble vegetable liquid instead of grease conventionally used at the request of preventing contamination of the soil and surrounding environment. The cost of wasted application liquid that flows down is therefore not negligible, and there is a problem of wheel slippage due to the excessive liquid application.

Furthermore, since the conventional nozzle block 140 is supported on the bracket 149 from below, when the treading pressure from the wheel is applied, a load is applied clockwise in FIG. 9, resulting in a gap between the nozzle block 140 and the rail. The application liquid then flows into the gap, resulting in further wasted application liquid.

Patent Document 1: Japanese Utility Model Publication No. 53-10641

Patent Document 2: Japanese Patent Laid-Open No. 2002-275806

Patent Document 3: Japanese Patent Laid-Open No. 2003-127858

DISCLOSURE OF THE INVENTION

The present invention has been made to solve the above problems in the conventional device for applying oil on a rail, and a first object of the present invention is to provide a device for applying liquid on a rail capable of minimizing wasteful flowing down of expensive application liquid to suppress the total amount of discharge of the liquid, reducing costs and further suppressing occurrence of environmental contamination, and preventing slippage of a wheel due to excessive liquid application.

A second object of the present invention is to provide a device for applying liquid on a rail capable of preventing a gap from being created between a nozzle block and a rail due to the treading pressure from a wheel and application liquid from flowing into the gap in a wasteful manner.

To achieve the first object, the invention according to claim 1 proposes a device for applying liquid on a rail including a tank, a liquid discharge pump for receiving supply of application liquid from the tank and performing a liquid discharge operation as a wheel passes, and a liquid application unit for discharging the application liquid onto a rail upon being supplied with the liquid from the liquid discharge pump. The liquid application unit has a nozzle block having a large number of nozzle holes arranged in the upper surface of the nozzle block, and the nozzle block has on its end section a hole-less end section where no nozzle hole is provided.

To achieve the second object, the invention according to claims 2 and 3 proposes a device for applying liquid on a rail in which the nozzle block is pressed and supported from diagonally below by a nozzle block support device that holds a base of the rail from below in such a way that the rail-side edge of the top surface of the nozzle block is always in close contact with the tread of the rail.

In a preferred embodiment, in the nozzle block support device, one end thereof is hooked to the base of the rail and the other end has a securing bolt for securing the nozzle block support device to the rail and a pressing bolt for pressing the nozzle block from diagonally below.

The nozzle block support device may be disposed in such a way that it extends across a runway rail and a guardrail. The hole-less end section is disposed at least at a front end section in the direction in which a vehicle is traveling. The liquid discharge pump may be mechanically driven by the treading pressure from the wheel, or may be electrically driven by a solar battery or an AC power supply.

The nozzle block in the device for applying liquid on a rail according to the present invention has the hole-less end section at the front end section of the nozzle block in the direction in which a vehicle is traveling and application liquid discharged on a rail in the hole-less end section is held and used without any waste, thus providing financial advantages of a reduced total amount of discharge of application liquid and hence reduced cost for the application liquid.

Furthermore, the nozzle block in the device for applying liquid on a rail according to the present invention is pressed and supported from diagonally below by the nozzle block support device, in which one end thereof is hooked to the base of the rail and the other end has a securing bolt for securing the nozzle block support device to the rail and a pressing bolt for pressing the nozzle block from diagonally below, in such a way that the rail-side edge of the top surface of the nozzle block is always in close contact with the tread of the rail. This configuration prevents a gap from being created between the rail-side edge of the top surface of the nozzle block and the tread of the rail and hence the application liquid from flowing down through the gap in a wasteful manner, thus providing an advantage of preventing increase in cost for the application liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing the whole configuration of the device for applying liquid on a rail according to the present invention;

FIG. 2 is a longitudinal cross-sectional view showing an exemplary configuration of a liquid discharge pump in the device for applying liquid on a rail according to the present invention;

FIG. 3 shows the operation of the liquid discharge pump in the device for applying liquid on a rail according to the present invention;

FIG. 4 is a schematic view showing another exemplary configuration of the liquid discharge pump in the device for applying liquid on a rail according to the present invention;

FIG. 5 is a perspective view showing the configuration of a liquid application unit in the device for applying liquid on a rail according to the present invention;

FIG. 6 is a side view showing the configuration of the liquid application unit in the device for applying liquid on a rail according to the present invention;

FIG. 7 is plan view of the main portion showing the configuration of the liquid application unit in the device for applying liquid on a rail according to the present invention;

FIG. 8 is a side view showing another configuration of the liquid application unit in the device for applying liquid on a rail according to the present invention; and

FIG. 9 is a side view showing a liquid application unit in a conventional device for applying liquid on a rail.

BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the device for applying liquid according to the present invention includes a tank 1 that is disposed near a rail 32 and stores application liquid, a liquid discharge pump 2 fixed to a side or a base 32 a of the rail 32, the number of the liquid discharge pumps 2 being typically plural, and liquid application units 3 disposed along the rail, the number of the liquid application units 3 is the same as that of the liquid discharge pumps 2. The liquid application unit 3 is disposed downstream of the liquid discharge pump 2 viewed in the direction indicated by the arrow in FIG. 1 in which a vehicle is traveling.

The tank 1 stores application liquid to be applied on a rail. An example of the tanks 1 is configured such that a pressing lid having an appropriate weight abuts the surface of the liquid to always pressurize the stored application liquid so that the application liquid is transported to the liquid discharge pump 2 under the influence of the pressure. The capacity of the tank is typically 10 to 20 liters. A tank of this kind is disclosed, for example, in Japanese Patent Laid-Open No. 11-293602.

Examples of the liquid discharge pump 2 include a pump mechanically driven by the treading pressure from a wheel and a pump electrically driven by a solar battery or an AC power supply as a power supply.

In the case of a mechanically driven pump shown in FIG. 2, the liquid discharge pump 2 includes a cylinder 6 through which application liquid to be supplied on a rail flows, an upper lid 7 that closes the upper side of the cylinder 6, a lower lid 7 a that closes the lower side of the cylinder 6, and a piston mechanism 8 that moves upward and downward in the cylinder 6.

The cylinder 6 is partitioned at some middle point to form upper and lower application liquid compartments. The upper application liquid compartment is a buffer liquid compartment 9 and the lower application liquid compartment is a liquid transportation compartment 10. A piston rod 11 of the piston mechanism 8 that moves upward and downward in the cylinder 6 has an upper piston 12 that slides in the upper buffer liquid compartment 9 and a lower piston 13 that slides in the lower liquid transportation compartment 10.

The buffer liquid compartment 9 has an upper liquid port 14 and a lower liquid port 15. One of the liquid ports, the liquid port 14, is a port through which the application liquid flows to and from an upper compartment 16 for the upper piston 12, and the other liquid port, the liquid port 15, is a port through which the application liquid flows to and from a lower compartment for the upper piston 12. The liquid ports 14 and 15 are connected to each other via an annular passage 19 provided with a check valve 18 and form a loop circuit including the upper and lower compartments 16 and 17 (see FIG. 3).

In the loop circuit including the buffer liquid compartment 9, the application liquid filled in the lower compartment 17 is pressurized by the upper piston 12 and pushed out at once in response to a quick downward action of the piston rod 11 when the treading pressure is applied by a wheel. The check valve 18 is then opened, so that the application liquid flows through the annular passage 19 into the upper compartment 16.

On the other hand, when the treading pressure on the piston rod 11 is released and the upper piston 12 goes up, the application liquid in the upper compartment 16 cannot flow backward through the annular passage 19 because the check valve 18 blocks the flow, so that the application liquid moves through a gap 20 (or choke) into the lower compartment 17. In this case, since the flow resistance is large, the moving speed of the application liquid from the upper compartment 16 to the lower compartment 17 is slow, resulting in a gentle upward action of the piston mechanism 8.

In the liquid transportation compartment 10, there are an upper liquid entrance port 25 and an upper liquid exit port 26 located on the upper side, as well as a lower liquid entrance port 27 and a lower liquid exit port 28 located on the lower side. The application liquid supplied from the upper liquid entrance port 25 to the liquid transportation compartment 10 flows into the space over the lower piston 13, and the application liquid supplied from the lower liquid entrance port 27 to the liquid transportation compartment 10 flows into the space under of the lower piston 13 (see FIG. 3). A conduit 21 connected to the upper liquid exit port 26 and a conduit 22 connected to the lower liquid exit port 28 are integrated, and the integrated conduit extends to the liquid application unit 3.

Each of the upper liquid entrance port 25 and the lower liquid entrance port 27 is connected to a tank-side liquid transportation tube 4 extending from the tank 1 via a check valve 5 a. The capacity of the space over the lower piston 13 and the capacity of the space under the lower piston 13 in the liquid transportation compartment change according to the upward and downward action of the piston rod 11. That is, the capacity of the space under the lower piston 13 is maximized when the piston rod 11 is at the upper end, while minimized when the piston rod 11 is at the lower end.

The piston rod 11 is usually pushed upward by a return spring 29 disposed between the lower lid 7 a and the lower surface of the lower piston 13 and thus situated at the upper end. On the other hand, when a train passes, the piston rod 11 receives the treading pressure from a wheel 31 and reaches the lower end for a moment. The tip of the piston rod 23 that comes in direct contact with the wheel 31 is preferably shaped into a hemisphere for reducing impact.

To attach the liquid discharge pump 2 to the rail 32, the cylinder 6 of the liquid discharge pump 2 may be directly secured to a side or a base 32 a of the rail 32 by fastening a bolt or the like. The liquid discharge pump 2 is preferably secured to the rail 32, for example, via an L-shaped pump support member 33 (see FIGS. 2, 6 and 7).

When a motorized pump is employed as the liquid discharge pump 2, a trochoid pump 72 directly connected to a motor 71 is used. In this case, the liquid discharge pump 2 includes the motor 71, the trochoid pump 72, a solar battery 73 or an AC power supply, a controller 74, and a photoelectric sensor 75 (FIG. 4).

In this case, the photoelectric sensor 75 senses the approach of a vehicle. Based on this sensing operation, the controller 74 controls the motor 71. The trochoid pump 72 is operated according to a timer setting, for example, for a period of 1 to 10 seconds, and pumps a predetermined amount of application liquid to the liquid application unit 3. After the specified time has been passed, the trochoid pump 72 immediately halts and stops transporting the liquid.

The configuration of the liquid application unit 3 will be described with reference to FIGS. 5 to 8. The liquid application unit 3 is paired with the liquid discharge pump 2, and the number of the liquid application units 3 to be installed is the same as that of the liquid discharge pumps 2, which is typically plural. The liquid application unit 3 has a nozzle block 40 that has an appropriate length and a shape that can be in close contact along the outer track-side head section of the rail.

The nozzle block 40 is installed in such a way that the top surface thereof is slightly inclined downward from the outer side (the left side in FIG. 6) toward the rail 32 in the width direction and the rail-side edge 40 b is substantially flush with the top surface of the rail 32. Application liquid present on the top surface of the nozzle block 40 is therefore guided onto the tread of the rail 32.

An oil storage pipe 41 with openings formed at fixed intervals is buried in the nozzle block 40, and nozzle holes 43 that communicate with the openings and are open through the top surface of the nozzle block 40 are formed in the nozzle block 40 such that the nozzle holes 43 are inclined toward the rail 32 by about 45 degrees (see FIG. 6).

The nozzle holes 43 in the nozzle block 40 in the device according to the present invention are not formed at an end section (one end section or both end sections) of the nozzle block 40. A hole-less end section 40 a where no nozzle hole 43 is formed is typically provided only at the front end section in the direction in which a train is traveling. However, when the installation site is a slope, for example, and the rear end section is lower than the intermediate portion, the hole-less end sections 40 a may be provided at the rear end section as well as at the front end section.

By thus providing the hole-less end section 40 a where no nozzle hole 43 is formed, even when the application liquid discharged from the end section-side nozzle holes 43 on the rail 32 flows forward or outward due to the slope of the rail 32 and the passage of a wheel, the above configuration prevents the discharged application liquid from immediately flowing down in a wasteful manner. That is, the application liquid discharged on the rail 32 from the nozzle holes 43 situated near the hole-less end section 40 a is guided toward the rail 32 along the top surface of the hole-less end section 40 a due to the slope in the longitudinal direction and the slope in the width direction of the nozzle block 40, so that the application liquid can be used without any waste all the way to the tip of the nozzle block 40.

To reliably provide the above effect, it is necessary to prevent creation of a gap, through which the application liquid flows down, between the rail-side edge 40 b of the top surface of the nozzle block 40 and the tread side surface of the rail 32 that comes in close contact with that edge. To this end, in the present invention, the nozzle block 40 is supported at a plurality of locations by pressing the nozzle block 40 diagonally upward toward the top of the rail 32 instead of pressing the nozzle block 40 vertically upward as conventionally done.

That is, the nozzle block support device 50 according to the present invention includes a body 51 that surrounds the base 32 a of the rail 32 from below. The front end of the body 51 is curved with a small radius (front-end curved portion 53) in such a way that the front end holds one side edge of the base 32 a, and the rear end of the body 51 is curved with a large radius (rear-end curved portion 52) in such a way that the rear end is oriented diagonally upward toward the top of the rail 32, specifically, toward the lower portion of the side surface 32 b of the head of the rail 32. The body 51 is preferably configured such that it becomes thicker toward the rear-end curved portion 52.

A securing bolt 54 and a pressing bolt 55 are provided at the end section of the rear-end curved portion 52 in such a way that they cross at right angles but are not in contact with each other. The securing bolt 54 is screwed into the end section of the rear-end curved portion 52 through a nut 56 fixed thereto, and a securing block 57 shaped such that it fits with the end section of the base 32 a of the rail 32 is provided at the tip of the securing bolt 54. The securing bolt 54 presses the securing block 57 toward the base 32 a of the rail 32 while rotating free with respect to the securing block 57.

In an example shown in FIG. 8, a guardrail 61 runs parallel to the rail 32. In this case, the body 51 extends for a long distance and the front-end curved portion 53 holds the base of the guardrail 61.

In the above configurations, when the securing bolt 54 is rotated, the nut 56 is fixed and hence is not rotated, so that the securing bolt 54 is screwed through the nut 56. This action presses the rear-end curved portion 52 in the direction away from the rail 32. As a result, the front-end curved portion 53 securely holds the edge of the base 32 a of the rail 32, so that the body 51 is securely fixed to the rail 32.

A female threaded block 58 is provided on the rear-end curved portion 52, and the pressing bolt 55 is screwed through the female threaded block 58 toward the lower portion of the side surface 32 b of the head of the rail 32. At the tip of the pressing bolt 55, there is provided a receiver 60 that has a seat conforming to the tip of the pressing bolt 55 and abuts the outer side and the bottom of the nozzle block 40, and the pressing bolt 55 presses the receiver 60 toward the nozzle block 40 while rotating free with respect to the receiver 60.

In such a configuration, when the pressing bolt 55 is screwed, the nozzle block 40 is pressed and supported diagonally upward by the receiver 60. Therefore, the treading pressure from a wheel will not tilt the nozzle block 40 counterclockwise in FIG. 9, and there will be no gap between the rail-side edge 40 b and the rail tread.

Although the present invention has been described in some detail with reference to the most preferable embodiment, it is apparent that a variety of different embodiments can be configured without departing from the spirit and extent of the present invention. The present invention is therefore not limited to specific embodiments thereof except those set forth in the accompanying claims. 

1. A device for applying liquid on a rail comprising: a tank; a liquid discharge pump for receiving supply of application liquid from the tank and performing a liquid discharge operation as a wheel passes; and a liquid application unit for discharging the application liquid onto a rail upon being supplied with the liquid from the liquid discharge pump, wherein the liquid application unit has a nozzle block having a large number of nozzle holes arranged in the upper surface of the nozzle block, and the nozzle block has on its end section a hole-less end section where no nozzle hole is provided.
 2. The device for applying liquid on a rail according to claim 1, wherein the nozzle block is pressed and supported from diagonally below by a nozzle block support device that holds a base of the rail from below in such a way that the rail-side edge of the top surface of the nozzle block is always in close contact with the tread of the rail.
 3. A device for applying liquid on a rail comprising: a tank; a liquid discharge pump for receiving supply of application liquid from the tank and performing a liquid discharge operation as a wheel passes; and a liquid application unit for discharging the application liquid onto a rail upon being supplied with the liquid from the liquid discharge pump, wherein the liquid application unit has a nozzle block having a large number of nozzle holes arranged in the upper surface of the nozzle block, the nozzle block has on its end section a hole-less end section where no nozzle hole is provided, and the nozzle block is pressed and supported from diagonally below by a nozzle block support device that holds a base of the rail from below in such a way that the rail-side edge of the top surface of the nozzle block is always in close contact with the tread of the rail.
 4. The device for applying liquid on a rail according to claim 2 or 3, wherein in the nozzle block support device, one end thereof is hooked to the base of the rail and the other end has a securing bolt for securing the nozzle block support device to the rail and a pressing bolt for pressing the nozzle block from diagonally below.
 5. The device for applying liquid on a rail according to any of claims 1 to 4, wherein the hole-less end section is disposed at least at a front end section in the direction in which a vehicle is traveling.
 6. The device for applying liquid on a rail according to any of claims 2 to 4, wherein the nozzle block support device is disposed in such a way that it extends across a runway rail and a guardrail.
 7. The device for applying liquid on a rail according to claim 1, wherein the liquid discharge pump is mechanically driven by the treading pressure from the wheel.
 8. The device for applying liquid on a rail according to claim 1, wherein the liquid discharge pump is electrically driven by a solar battery or an AC power supply. 